Optimum Annealing Temperature Research Articles

Structural and electrical properties of Sb-doped SnO2 thin films prepared by metal organic decomposition

Sb-doped SnO2 thin films were prepared by metal organic decomposition through pyrolysis of organic acid salts. The dependence of the structural and electrical properties of the films on the Sb concentration, annealing temperature, and film thickness was investigated. A polycrystalline rutile structure was confirmed for all samples using X-ray diffraction and atomic force microscopy measurements. Structural properties of the samples improved with an increase of the annealing temperature, and deteriorated with an increase of the Sb concentration. The resistivity of the Sb-doped SnO2 thin films decreased above 3.0 at.% Sb doping. It was suggested that for each film thickness, there was an optimum annealing temperature in terms of the resistivity. The lowest resistivity (3.6 × 10−3 Ωcm) was obtained for the sample with a Sb concentration of 3.0 at.% and a film thickness of 550 nm, that was annealed at 900 °C.

Kondisi optimal PCR untuk mendeteksi gen FimH isolat klinis Escherichia coli penyebab infeksi saluran kemih

Background: Urinary tract infection is one of the most common infectious diseases and the second most common infection after respiratory tract infection. Bacteria are the most common cause of urinary tract infections in more than 95% of cases. Escherichia coli is the most common bacteria that found in 80-90% of cases of urinary tract infection. The critical virulence factor of Escherichia coli is the type 1 fimbriae with the adhesion subunit, fimH, plays an essential role in the pathogenesis of urinary tract infection.Aim: The research aims to obtain the optimal condition of PCR in detecting the fimH gene with modification of annealing temperature in the PCR process.Method: This study used a sample of fimH DNA genes from clinical isolates of E. coli causing UTI. The second PCR used an annealing temperature of 57°C and a third PCR using an annealing temperature of 64°C. The electrophoresis results are then viewed with an ultraviolet transilluminator. Result: The optimization finding showed that the annealing temperature of 52 °C, 57 ° C, and 64°C could detect the fimH gene where the higher the temperature used by Tm, the less the specificity produced.Conclusion: The optimum annealing temperature of PCR to identify the fimH gene from E.coli causes the UTI is in the temperature of 64°C with better specificity than of 52°C. The annealing temperature of 64°C indicates the lowest specificity.

Effects of Ti Addition on the Microstructure and Tensile Properties of China Low Activation Martensitic Steel for Nuclear Fusion Reactors

Herein, the effects of Ti, a low activation alloying element, in the range of 0.01–0.11 wt% on the microstructure, mechanical properties, and impact toughness of China low activation martensitic steel are studied. Fine prior austenite grains and some δ‐ferrite phases are observed for alloys with a Ti content of 0.05 and 0.11 wt%, respectively. The 0.05Ti alloy exhibits a higher yield strength (YS) compared with the 0.01Ti and 0.11Ti alloys because of the additional precipitation hardening by the fine MX particles and small grain size. When the samples are tempered at 650 °C, nanosized (Ti, W) C MX carbides with a size of approximately 20 nm precipitate, leading to an increase in the ultimate tensile strength (UTS) and YS of the 0.05Ti alloy. The ductile‐to‐brittle transition temperature (DBTT) decreases when the Ti content increases to 0.05 wt%. However, the DBTT of the 0.11Ti alloy increases with the precipitation of the δ‐ferrite phase. On the basis of the performance of the steels, the optimal Ti content is found to be approximately 0.05 wt% and the optimal tempering temperature is found to be 650 °C.

Optimisation of a droplet digital PCR for strain specific quantification of a probiotic Bifidobacterium animalis strain in poultry feed

The use of probiotics in animal nutrition to provide health benefits is widely accepted. Bifidobacterium animalis (BAN) is an example of a commonly used beneficial strain. BAN is applied in a multi-strain feed additive for poultry. As part of the increased demand for tracking and tracing of feed additives within modern quality management, it is crucial to determine the quantity of the active strain after mixing the probiotic product into feed. A real-time PCR protocol, already developed some years ago, was replaced with a Droplet Digital PCR (ddPCR) assay, as this third generation PCR method is known for higher precision, sensitivity and does not require standard curves. Each sample is partitioned into thousands of small subsamples that are measured individually and an absolute result value for each sample is extrapolated via Poisson distribution. The following parameters were evaluated for the ddPCR assay: optimal annealing temperature (59 °C), concentration of primers (500 nM) and probe (400 nM), and PCR cycle number (50 cycles). The linearity of the optimised ddPCR assay was tested with BAN DNA extracted from pure culture. The obtained standard curve was linear (R2 = 0.9982) and the efficiency (E) of the method was 99.98%. To finalise the development, the Limit of Blank (LoB = 9.17 × 102 copies g−1), Limit of Detection (LoD = 1.15 × 103 copies g−1) and Limit of Quantification (LoQ = 1.57 × 103 copies g−1) for the assay were determined using poultry feed free of BAN and feed spiked with different concentrations of the strain. A BAN strain-specific, probe-based ddPCR assay for the quantification in poultry feed was developed.

Near-infrared electroluminescence from metal-oxide-semiconductor devices with erbium-doped gadolinium oxide on silicon

Metal-oxide semiconductor (MOS) devices with Er-doped gate oxides as the light-emitting layers are considered as one of the most promising strategies to achieve silicon-based electroluminescence (EL). In this work, Er-doped Gd2O3 (Gd2O3:Er) films were grown on silicon by atomic layer deposition. The main cubic Gd2O3 phase and hexagonal Gd9.33(SiO4)6O2 phase were obtained in Gd2O3:Er films after thermal annealing treatment. Moreover, 900 °C and 1100 °C were identified as the optimal annealing temperatures for the photoluminescence from Gd2O3 phase and Gd9.33(SiO4)6O2 phase films, respectively. Based on this, the MOS devices were further fabricated with annealed Gd2O3:Er films as the light-emitting layers. Analysis on the current-voltage characteristics of the MOS devices indicates that the electron transportation at the EL-enabling voltages is dominated by Fowler-Nordheim tunneling. More importantly, Er-related EL in the near-infrared region from MOS devices was detected at ∼1530 nm as a function of the Er dopant concentration. The external quantum efficiency reaches 4% for the 900 °C-annealed Gd2O3:0.47%Er MOS device and 8% for the 1100 °C-annealed Gd9.33(SiO4)6O2:2.97% Er MOS device. It is believed that this work has laid the foundation for developing near-infrared silicon-based emitters using Gd2O3:Er films.

Growth and properties analysis of AlxGa2-xO3 thin film by radio frequency magnetron sputtering using Al/Ga2O3 target

In this work, (AlxGa1-x)2O3 thin films were grown on Al2O3 (0001) substrate by radio frequency magnetron sputtering using Al/Ga2O3 target. The analysis of crystalline structure, morphology, transmittance and bandgap after various annealing temperatures were investigated in detail. The films were oriented along (2—01) plane, and the crystalline quality improved with increasing annealing temperature. The stoichiometries of films can be regard as (Al0.33Ga0.67)2O3 according to X-ray photoelectron spectroscopy and the additional compressive stress in the sample which annealed at 900 °C was certified. The bandgap of annealed films was totally decreased due to increasing magnitude of compressive stress and grain size. Therefore, these results may suggest the way to tune the band gap of β-(AlxGa1-x)2O3 films by varying the residual stress through annealing and indicate the optimum annealing temperature for (Al0.33Ga0.67)2O3 thin films is about 800 °C.

Optimization of annealing treatment and comprehensive properties of Cu-containing Ti6Al4V-xCu alloys

The Ti6Al4V-Cu alloy was reported to show good antibacterial properties, which was promising to reduce the hazard of the bacterial infection problem. For the purpose of preparing Ti6Al4V-Cu alloy with satisfied comprehensive properties, it’s important to study the heat treatment and the appropriate Cu content of the alloy. In this study, high Cu content Ti6Al4V-xCu (x = 4.5, 6, 7.5 wt%) alloys were prepared, and firstly the annealing heat treatments were optimized in the α+β+Ti2Cu triple phase region to obtain satisfied tensile mechanical properties. Then the effect of Cu content on the tribological property, corrosion resistance, antibacterial activity and cytotoxicity of the Ti6Al4V-xCu alloys were systematically studied to obtain the appropriate Cu content. The results showed that the optimal annealing temperatures for Ti6Al4V-xCu (x = 4.5, 6, 7.5 wt%) alloys were 720, 740 and 760 °C, respectively, which was resulted from the proper volume fractions of α, β and Ti2Cu phases in the microstructure. The additions of 4.5 wt% and 6 wt% Cu into the medical Ti6Al4V alloy could enhance the wear resistance and corrosion resistance of the alloy, but the addition of 7.5 wt% Cu showed an opposite effect. With the increase of the Cu content, the antibacterial property was enhanced due to the increased volume fraction of Ti2Cu phase in the microstructure, but when the Cu content was increased to 7.5 wt%, cytotoxicity was presented. A medium Cu content of 6 wt%, with annealing temperature of 740 °C make the alloy possesses the best comprehensive properties of tensile properties, wear resistance, corrosion resistance, antibacterial property and biocompatibility, which is promising for future medical applications.

Optical and electrical properties of ZnO/Mo/ZnO multilayer films processed at different annealing temperatures

ZnO/Mo/ZnO transparent conductive thin films are deposited on Corning glass substrates using an RF magnetron sputtering system. The optical and electrical properties of the thin films are then examined following annealing for 40 min at temperatures ranging from 200 to 450 °C. It is shown that the resistivity of the ZnO/Mo/ZnO films has a low and reducing value at annealing temperatures up to 300 °C. However, the resistivity increases dramatically as the annealing temperature is further increased to 450 °C. The average transmittance of the annealed films generally increases with an increasing annealing temperature as the result of a larger grain size. For an annealing temperature of 450 °C, the maximum transmittance is equal to approximately 85%. Overall, the results suggest that the optimal annealing temperature for the present ZnO/Mo/ZnO films is 300 °C, which results in an electrical resistivity of 6.44 × 10−3 Ω-cm and an optical transmittance of 80%.

Effect of annealing temperature on microstructure and bond strength of cast-rolling Cu–Al clad plates

Effect of different annealing temperatures on evolution of microstructure in copper-aluminum clad plates prepared by cast-rolling were investigated using scanning and transmission electrical microscopy, and x-ray diffraction. Peeling tests were conducted to characterize the bond strength of prepared clad plates. Results showed that with the increase in annealing temperature, the bond strength of the 8 mm thick copper-aluminum clad plates first increased and then decreased. When the annealing temperature was 250 °C–300 °C for 3 h, CuAl2 was formed at the interface, promoting atomic diffusion and improving the bond strength. However, when the annealing temperature was 300 °C–400 °C for 3 h, providing enough energy for a new Cu9Al4 intermetallic phase formed at the interface, and the thickness of the interface layer increased from about 1 μm to 11 μm, while the bond strength decreased from 42 ± 0.8 N·mm−1 to 12 ± 1 N·mm−1. The fracture pattern of the clad plates extensible to brittle with the annealing temperatures from 300 °C to 450 °C for 3 h. According to the experimental results, the optimal annealing temperature for copper-aluminum clad plates prepared by cast-rolling is 300 °C for 3 h.

Preparation and characterization of flaky FeSiAl composite magnetic powder core coated with MnZn ferrite

The flattening of FeSiAl soft magnetic powder was achieved by ball milling process, and MnZn/FeSiAl composite magnetic powder core was prepared by press molding. The effect of different coating amount of MnZn ferrite on the soft magnetic properties of FeSiAl was studied. At the same time, the optimal stress-relieving annealing temperature of the composite magnetic powder core is revealed. The results showed that the addition of MnZn ferrite affected the magnetic properties such as saturation magnetization (Ms), initial permeability (μi) and power loss (Pcm) of FeSiAl soft magnetic. With the increase of MnZn ferrite addition content, the saturation magnetization of composites decreased gradually, and the magnetic permeability increased first and then decreased, and the loss decreased first and then increased. When the addition content of MnZn ferrite was 5%, the permeability reached the maximum, which was 28.1% higher than that of the pure FeSiAl magnetic powder core under the same conditions. At the same time, the loss was the lowest, which was 13.3% lower than the pure FeSiAl powder core under the same conditions. When the annealing temperature is around 650 °C, the magnetic powder core has the largest magnetic permeability and the lowest loss.

Surface Modifications on LiCoO2-Based Cathodes for High-Density Lithium-Ion Batteries with Long Cycle Life

Commercial rechargeable lithium-ion batteries (LIBs) use LiCoO2(LCO) as the cathode, which shows relatively low energy capacity (~140 mAh/g) and suffers poor cycle life performance. To develop next-generation LIBs with high voltage, high capacity and long cycle life, surface modifications on cathodes have been applied. We start with thin layers of Li2SrSiO4(LSSO) synthesized from sol-gel method to coat on the LCO surfaces and to test the optimal conditions, namely thickness and annealing temperature, for LIB performances in both half-cell and full cell configurations. LSSO is predicted by theoretical calculation1as the best surface coating but our results show that LSSO alone cannot lead to improved performance at 4.5 V cut-off voltage but a combination of LSSO and Al2O3could yield the best protection and performance. Following a series of electrochemical tests, electron microscopy and synchrotron X-ray characterizations, we provide some insights about mechanism in our surface modification. [1] M. Aykol et al., Nature Communications, 7, 2016, 13779

Structural Properties and Sensing Characteristics of YbTaO4 Sensing Membranes

In this paper, we developed YbTaO4 sensing membranes for use in a solid-state electrolyte–insulator–semiconductor (EIS) pH sensor. Impact of rapid thermal annealing (RTA) treatment on the structural and sensing properties of the YbTaO4 sensing membranes deposited through reactive co-sputtering onto Si substrates was investigated. X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy were employed to examine the structural, morphological, and chemical features, respectively, of the YbTaO4 sensing films annealed at three RTA temperatures (700, 800 and 900 °C). The YbTaO4 EIS sensor annealed at the 800 °C exhibited a super-Nernstian response of 71.17 mV/pH within the pH range of 2–12. It also showed the lowest hysteresis voltage (<1 mV) and the lowest drift rate (0.22 mV/h) among the these RTA temperatures. Presumably, the optimal annealing temperature improved the stoichiometry of YbTaO4 film and increased its (-131)-oriented nanograin size. Figure 1

Electrochemical evaluation of the corrosion protectiveness and porosity of vacuum annealed CrAlN and TiAlN cathodic arc physical vapor deposited coatings

AbstractThe corrosion behavior of cathodic arc physical vapor deposited CrAlN and TiAlN coatings were examined in 1 M HCl solution before and after vacuum annealing at 700, 800, 900, and 1000 °C. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods were used to study the corrosion behavior and porosity of the coatings in comparison with the bare steel substrate (304SS). Structural and mechanical characterization of the coatings were also conducted. It is found that with increasing annealing temperature, the mechanical properties of TiAlN increased due to age hardening caused by spinodal decomposition while the hardness of CrAlN decreased as result of relaxation. Similarly, EIS and PDP results revealed that the as‐deposited and annealed coatings offer higher corrosion resistance as compared to the bare 304SS substrate. The coatings susceptibility to corrosion is reduced after annealing as indicated by the increasing nobility of Ecorr. Both PDP and EIS tests revealed that CrAlN coating annealed at 1000°C exhibited superior corrosion resistance properties. It is found that the reduced current density for CrAlN coating annealed at 1000°C was due to the reduction in the porosity. Annealed TiAlN coating follows similar behavior until an optimum annealing temperature of 800°C. Beyond this temperature, porosity enlargement and an increase in the number of pores subsequent to structural changes deteriorated the corrosion resistance of TiAlN coating.

Nebulization using ZnO/Si surface acoustic wave devices with focused interdigitated transducers

Propagation of surface acoustic waves (SAWs) on bulk piezoelectric substrates such as LiNbO3 and quartz, exhibits an in-plane anisotropic effect due to their crystal cut orientations. Thin film SAW devices, such as those based on ZnO or AlN, offer potential advantages, including isotropic wave velocities in all in-plane directions, higher power handling capability, and potentially lower failure rates. This paper reports experimental and simulation results of nebulization behaviour for water droplets using ZnO/Si surface acoustic wave devices with focused interdigital transducers (IDTs). Post-deposition annealing of the films at various temperatures was applied to improve the quality of the sputtering-deposited ZnO films, and 500 °C was found to be the optimal annealing temperature. Thin film ZnO/Si focused SAW devices were fabricated using the IDT designs with arc angles ranging from 30° to 90°. Nebulization was significantly enhanced with increasing the arc angles of the IDTs, e.g., increased nebulization rate, reduced critical powers required to initialise nebulization, and concentration of the nebulised plume into a narrower size of spray. Effects of applied RF power and droplet size have been systematically studied, and increased RF power and reduced droplet size significantly enhanced the nebulization phenomena.

Droplet digital PCR improves urinary exosomal miRNA detection compared to real-time PCR

ObjectQuantification of urinary miRNAs can be challenging especially for low abundance miRNAs. We aimed to optimize the quantification of urinary exosomal miRNAs and compare the performance efficiency between droplet digital PCR (ddPCR) and real-time quantitative PCR (qPCR). MethodsWe optimized a number of parameters for ddPCR such as annealing temperatures, annealing time and PCR cycle number. We also compared the performance of ddPCR and qPCR. ResultsBy comparing the fluorescence amplification separation, the optimal annealing temperature was 59 °C, optimal annealing time was 60s and optimal cycle number was 45 for measuring urinary exosomal miRNAs. ddPCR had much higher technical sensitivity compared to qPCR. The minimal detectable concentration of miR-29a was <50 copies/μL by ddPCR compared to 6473 copies/μL for qPCR. Also, ddPCR generated more consistent results for serially diluted samples compared to qPCR. ddPCR generated smaller within-run variations than qPCR though this did not reach statistical significance. It also resulted in better reproducibility with smaller between-run variations. ConclusionsOptimization of urinary exosomal miRNA ddPCR assay is dependent on assessing key variables including experimental annealing temperature and time as well as the number of PCR cycles. ddPCR has a higher sensitivity, reproducibility, and accuracy in comparison to qPCR.

Preparation Structure and Magnetic Properties of Mn-Doped ZnO Nanoparticles Prepared by Hydrothermal Method

In this research, manganese-doped ZnO (Zn0.99-xMnxO) nanoparticles were synthesized by hydrothermal method using the chemicals. The samples were annealed at 500 and 600 °C to figure out the optimum annealing temperature characterized by differential thermal analysis (DTA) method. Simultaneously with DTA analysis, the possible weight loss was observed by thermal gravimetric (TG) method and categorized the lost chemicals with varying temperature regions. The crystal structure with lattice parameters and the phases were determined by X-ray diffraction method. Microstrain (e), stress (σ), the dislocation density (δ), the locality of the atoms and their displacements (u), and the bond length (L) values were calculated by making use of lattice parameters. The particle morphologies were monitored by scanning electron microscope (SEM) technique and the elemental compositions of the samples were investigated and found that all peaks belong to Zn, Mn, and O elements. The magnetic properties of the samples were revealed using Quantum design PPMS measurement system and correlated with structural properties.

PCR effects of melting temperature adjustment of individual primers in degenerate primer pools.

Deep sequencing of small subunit ribosomal RNA (SSU rRNA) gene amplicons continues to be the most common approach for characterization of complex microbial communities. PCR amplifications of conserved regions of SSU rRNA genes often employ degenerate pools of primers to enable targeting of a broad spectrum of organisms. One little noticed feature of such degenerate primer sets is the potential for a wide range of melting temperatures between the primer variants. The melting temperature variation of primers in a degenerate pool could lead to variable amplification efficiencies and PCR bias. Thus, we sought to adjust the melting temperature of each primer variant individually. Individual primer modifications were used to reduce theoretical melting temperature variation between primers, as well as to introduce inter-cluster nucleotide diversity during Illumina sequencing of primer regions. We demonstrate here the suitability of such primers for microbial community analysis. However, no substantial differences in microbial community structure were revealed when using primers with adjusted melting temperatures, though the optimal annealing temperature decreased.

Pn junction formation by Si paste coated on metal substrates

In this work, p- and n-type Si pastes were prepared in a way by utilizing a planetary ball miller to pulverize Si source material. pn homojunction was formed by coating Si pastes onto metal substrates, followed by annealing under Ar or Ar + H2 atmosphere. The optimal annealing temperature was found to be around 1050 °C that exhibits the lowest resistivity. A typical rectifying property of diode with small photovoltaic was observed for the device fabricated. It is anticipated that Si pastes could have potential for low cost device fabrication such as solar cells. All Cz Si ingot growth procedures could be skipped, consequently it is expected that the manufacturing cost for solar cell can be greatly reduced.

Cyclic deformation behavior and microstructure evolution of high-carbon nano-bainitic steel at different tempering temperatures

Bainitic steel is applied in many cyclic loading projects due to its excellent comprehensive mechanical properties. In this study, the cyclic hardening/softening behavior and microstructure evolution of high-carbon nano-bainitic steel were investigated to analyze the cyclic deformation mechanism. Results showed that the optimal tempering temperature was determined to be at low temperature. During cyclic deformation, the retained austenite is transformed into martensite according to the Kurdjumov-Sachs (K-S) and Nishiyama-Wassermann (N-W) orientation relationships, and deformation twins are generated in the retained austenite. The cyclic deformation of high-carbon steels at a total strain amplitude of 0.6% manifests no obvious cyclic softening behavior after low-temperature tempering, mainly due to the high density of dislocation tangle around martensite and deformation twins induced by cyclic deformation.

Optimization of annealing temperature and the annealing effect on life time and stability of P3HT:PCBM-based organic solar cells

Post-production annealing which improves the power conversion efficiency of the P3HT:PCBM-based organic cells are very important process. Lots of various annealing temperatures and annealing times have been used for annealing process in previous studies but not any criteria was taken as a basis for determination of annealing temperature. In this study annealing temperature was optimized for annealing time of 3 min ITO-PEDOT:PSS/P3HT:PCBM/Al was fabricated at the weight ratio of 12:8 for P3HT:PCBM. Organic solar cells were annealed at different annealing temperatures in the range of 80 °C–160 °C. The variation of external quantum efficiency (EQE) with annealing temperature was obtained. The higher EQE was obtained at 120 °C. Thus, 120 °C was determined as optimum annealing temperature. The aging experiments were performed under constant humidity, illumination and atmospheric conditions. It has been observed that the post- product annealed at 120 °C solar cells have more longer life time and more stable compared with the non-annealed cell and other annealed solar cells.